JPS6226778B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an ultrasonic diagnostic apparatus, and more particularly to an electronic scanning type ultrasonic diagnostic apparatus that electronically controls and scans an ultrasonic beam.

Ultrasonic diagnostic equipment scans a predetermined tomographic plane within a patient's body with an ultrasound beam, receives echoes from various locations within the body, performs brightness modulation according to the intensity of the echo signal, and detects reflection points on the display surface. A tomographic image is obtained by displaying a bright spot at a position corresponding to the bright spot. Typical scanning methods include a linear type in which the ultrasonic beam is scanned in parallel or a sector type in which the ultrasonic beam is scanned in a fan shape, and conventional apparatuses are configured to perform only one of the scanning methods. FIG. 1 shows an outline of a linear scanning type device.
In this figure, 1 is #1, #2..., #nk (n and k
is a positive integer)
This is an array transducer with elements arranged in one row. A multiplexer 2 sequentially selects a fixed number (for example, k) of elements, and in the case of reception, echo signals from each element are added together in an adder circuit 4 via a focus delay circuit 3. The same applies to the case of wave transmission, and the delay circuit 3 works as a delay circuit for focusing the transmission signal.

FIG. 2 is a diagram for explaining the configuration of the sector type scanning method. In this figure, 1 is an array transducer as in FIG. 1, and 3 is a focusing delay circuit. 51 to 5k are deflection delay circuits, and the echo signal from the #1 element is sent to k delay circuits 5.
The echo signal from element #k passes through only one delay circuit 5k, so it has the least delay. By sequentially changing the delay time in this manner, the composite wavefront at the time of wave transmission and wave reception can be tilted and deflected by a predetermined angle. Each of the delay circuits 51 to 5k is of a variable delay type, and the delay time is set to 1.
By changing the angle for each ultrasonic beam, ultrasonic beams deflected at different angles are obtained and sector scanning is performed.

Furthermore, recently a scanning method called a compound type has been proposed. As shown in Figure 3, this method involves emitting ultrasonic beams deflected at a predetermined angle in parallel in sequence to complete one field, and in the next field, the beams are deflected at a different angle and scanned in parallel. In other words, it is a combination of the conventional sector type and linear type.

SUMMARY OF THE INVENTION An object of the present invention is to provide a multi-purpose electronic scanning ultrasonic diagnostic apparatus that can perform any of the above-mentioned linear, sector, and compound scanning methods with a single device.

Hereinafter, one embodiment of the present invention will be described with reference to FIG. In FIG. 4, the multiplexers 21 are #1, #k+1, #2k+1,...
#(n-1) Connected to select one of k+1 n elements. Similarly, the multiplexer 22 is #2, #k+2,..., #(n-1)k
+2, and the multiplexer 2k is connected to n elements #k, #2k, . . . , #nk. These k multiplexers 21~
The 2k output terminals are delay circuits 611 to 61, respectively.
connected to k. This delay circuit is a delay circuit with taps in which the delay time can be selected in stages, and each tap is connected to multiplexers 711-71k. The tap signals selected by the multiplexers 711-71k are sent to similar delay circuits 621-62k with taps. Each tap of the delay circuits 621 to 62k is connected to a multiplexer 72.
Selected from 1 to 72k. Each echo signal thus delayed is outputted via the adder circuit 4. Although FIG. 4 shows the configuration when receiving waves, the configuration is the same when transmitting waves, and one drive pulse is delayed and selected in k ways by delay circuits 611 to 61k and 621 to 62k. The configuration may be such that it is sent to k elements.

Delay circuits 611-61k and delay circuits 621-
62k consists of a delay line with, for example, 16 taps. It is assumed that the delay time per tap of the delay circuits 611 to 61k is Q, and the delay time per tap of the delay circuits 621 to 62k is 15Q. Then, 256 delay times of the quantization delay time Q are obtained by the multiplexers 711 to 71k and 721 to 72k. Multiplexers 711 and 721 are controlled by counter 81, and multiplexer 7
12,722 is controlled by counter 82. Multiplexers 71k and 72k are counters 8
k, and the other multiplexers are similarly controlled by corresponding counters. Each of the counters 81 to 8k is configured with an 8-bit counter, and the lower 4 bits of the output are sent to each of the multiplexers 711 to 71k, and the higher digit 4 bits are sent to the multiplexers 721 to 72k to issue a delay time selection command. do. Each count value of the counters 81 to 8k is a count value of a count up pulse sent through each of gates 91 to 9k controlled by the shift register 10.

Next, the operation will be explained starting from the case of linear scanning. In this case, the shift register 10 controls the gates 91 to 9k in advance, and the counters 81 to 9k use the data of the focus delay time as a count value.
Enter it in 8k. Elements #1 to #k are selected at the beginning of a certain field, and this k
The elements are driven to obtain one ultrasonic beam. When the scanning of this ultrasonic beam is completed, a shift pulse is sent to the multiplexer 21, and the multiplexer 21
Select 1. Therefore multiplexer 22,
23,..., 2k, 21 for k from #2 to #k+1
This means that 1 element has been selected. At this time, the counted values held in the counters 81, 82, . . .
3, the counter 8k is transferred to the counter 81. Therefore, at this time, one ultrasonic beam is formed from k elements #2 to #k+1. By repeating the above operations, linear scanning can be performed.

Next, sector-type scanning will be explained. In this case, it is assumed that, for example, k elements #1 to #k are selected by the multiplexers 21 to 2k. Multiplexers 21 to 2k maintain this state, and only elements #1 to #k are used. Here, a case will be described in which one ultrasonic beam deflected by a predetermined angle to the right in a certain field is formed from the k elements described above. In this case, first, +5V is applied to the right serial input terminal of the shift register 10 so that this input is always "1". Then add a shift light signal that tells you to shift to the right. Add a count-up pulse in this state. Initially, all gates 91-9k are open, so all counters 81-81k perform counting. When the counter 81 has counted a predetermined value, a shift clock is sent to the shift register 10 and the gate 91 is closed. Further, since the gates 92 to 9k are open, the counters 82 to 8k continue to count, and when the counter 82 reaches a predetermined count value, the next shift clock is sent and the "1" input in the shift register 10 is counted. ” and closes the gate 92. In this way, the gates are sequentially closed, and the counters 81 to 8k are made to hold count values corresponding to the necessary deflection delay time and focus delay time, respectively. All counters 81~
When the counter 8k has completed counting, the count value of the counter 81 is the smallest, and the count value of the counters 82, 83, . . . becomes larger, and the counter 8k takes the maximum value. In this way, a delay time corresponding to the count value held in the counters 81 to 8k is added to the echo signal from each element, and one ultrasonic beam deflected to the right by a predetermined angle is formed. Next, when forming ultrasonic beams with different deflection angles, the counters 81 to 8k and the shift register 10 are cleared once, and the count values of the deflection and focus delay times corresponding to the deflection angles are stored in the respective counters 81 to 8k. 8
The same operation as above is performed to maintain the value k. In this way, sector-shaped scanning is performed by changing the counts of the counters 81-8k for each ultrasonic beam having a different deflection angle. In addition, when deflecting in the opposite direction (for example, leftward), the leftward serial input of the shift register 10 may be set to "1" to give a shift left command.

When performing compound type scanning, the counter 81
~8k is made to hold count values corresponding to the deflection delay time and the focus delay time. Then, as in the case of linear scanning, multiplexers 21 to 2
Send the shift clock to k sequentially and start #1~
The elements to be selected are shifted one by one from #k, then from #2 to #k+1, and so on. At the same time, the count values of the counters 81 to 8k are shifted one by one from the counter 81 to the counter 82 and from the counter 82 to the counter 83. In this way, ultrasonic beams parallel to a certain angle are formed one after another while being deflected at a certain angle, and one field ends. Counter 8 in next field
1 to 8k and the shift register 10 are cleared once, and the counted values of the deflection delay time and focus delay time corresponding to other deflection angles are stored in the counters 81 to 8k.
hold it. Similarly, ultrasonic beams deflected at different angles from those in the previous field are successively formed in parallel, and the next field ends. In this way, a compound type scan is performed.

As described above with respect to the embodiments, the ultrasonic diagnostic apparatus of the present invention includes an array transducer consisting of nk ultrasonic transducer elements, where n and k are positive integers; 1
The first step of selecting one of the n elements of the (n-1)th, k+1st, ..., (n-1)th k+1st
(21 in FIG. 4), and a second multiplexer for selecting one of the n elements of the second, k+2, ..., (n-1) k+2.
multiplexer (22), and the third to kth multiplexers that similarly select one of the n elements.
multiplexers (23 to 2k), and k rewritable memory circuits (counter 8 in the embodiment) that hold delay time data regarding the k elements selected by the k multiplexers.
1 to 8k), and k delay circuits (in the embodiment, delay circuits 611, 621 to 6) connected to each of the k multiplexers and whose delay time is determined based on the data of each of the k storage circuits.
1k and 62k delay circuits) and the k memory circuits, respectively, and performs control to write data related to the delay time into each of the k memory circuits, and controls to transfer the contents of each of the memory circuits to other memory circuits. Since it has a control circuit (shift register 10 in the embodiment) for a storage circuit that performs a memory circuit, a single ultrasonic diagnostic device can perform linear, sector, or compound scanning, making it a versatile diagnostic tool. can be carried out, improving efficiency and reducing costs.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an outline of the configuration of a conventional linear scanning system, FIG. 2 is a block diagram showing an outline of a configuration of a conventional sector scanning system, and FIG. 3 is a block diagram showing an outline of a configuration of a conventional sector scanning system. FIG. 4 is a block diagram showing one embodiment of the present invention. 1...Array transducer, 2, 21~
2k, 711-71k, 721-72k...multiplexer, 3...delay circuit for focus, 4...addition circuit, 51-5k...delay circuit for deflection, 611-
61k, 621~62k...delay circuit with tap,
81-8k...Counter, 91-9k...Gate, 10...Shift register.

Claims (1)

[Claims] 1, where n and k are positive integers, an array transducer consisting of nk ultrasonic transducer elements, 1st, k+1st, ..., (n-1)k+1st a first multiplexer that selects one of the n elements;
a second multiplexer that selects one of the k+2th n elements; and a third to kth multiplexer that similarly selects one of the n elements;
a multiplexer, k rewritable memory circuits that hold delay time data regarding the k elements selected by the k multiplexers, and the k memory circuits connected to each of the k multiplexers. Control is performed to write data regarding the delay time into each of the k delay circuits whose delay time is determined based on the data of each of the circuits, and the k memory circuits, and the contents of each of the memory circuits are written to other memory circuits. An ultrasonic diagnostic apparatus comprising: a control circuit for a memory circuit that controls data transfer to a memory circuit;